package day6;

import java.util.Calendar;
import java.util.Collections;

/**
 * @author oldliu
 * @since 1.0
 */
   interface Test {
    int a=21;
    int b=33;
      void aaa();//实际上他是public
    public static void main(String[] args) {
        int aa[]=new int[3];
        aa.hashCode();

        Calendar a = Calendar.getInstance();
        a.set(2022, 0 , 0);
        System.out.println(a.getTime());
        String s1="abc"+"def";
        String s2=s1;
        System.out.println(s1==s2);
    }
}
